天津辛口镇分层地面沉降特征及成因

Characteristics and cause of layered land subsidence in Xinkou,Tianjin

使用分层标对不同层位不同岩性地层进行地面沉降分层监测是进行地面沉降规律与机理研究的重要方法。以天津市西青区辛口镇分层标为例,对2005年-2009年地面沉降分层监测数据进行了分析,发现研究区潜水-微承压、第Ⅱ、第Ⅲ含水层沉降量呈逐年减小趋势;潜水-微承压含水层及第Ⅰ承压含水层沉降量与本层地下水开采关系较小,其沉降量主要由介质弹性形变量组成;第Ⅳ承压含水层仍处于匀速沉降阶段,第Ⅱ、Ⅲ含水层削减开采量未对本层沉降起到抑制作用。研究结果可以为地下水开采布局调整提供依据。

Use of borehole benchmark is an important method to investigate the mechanism of layered land subsidence in different stratums. In this paper, the layered monitoring land subsidence data in Xinkou, Xiqing district of Tianjin City between 2005 and 2009 were analyzed. The results showed that the settlements of phreatic-feeble confined aquifer, the No. Ⅱ, and No. Ⅲ confined aquifers decrease annually; the settlements of phreatic-feeble confined aquifer and the No. I confined aquifer have insignificant relationship with the exploitation quantity, and they are mainly caused by elastic deformation; the settlements of the No. Ⅳ confined aquifer are still increasing uniformly and the reduction of exploitation quantity in the No. Ⅱ and No. Ⅲ confined aquifers cannot help restrain the settlements of the No. Ⅳ aquifer. The results can provide reference for the distribution adjustment of groundwater exploitation in this area.